Is The Defense Approaching Average? - *The Statistics Say Yes*

As a follow up to my last diary entry(Statistical Analysis of the Defense During B10 Play), I decided to do a comparitive analysis to a team considered an average defense generally speaking. For this particular comparison, I decided to use Penn State's defense as a baseline, based on the fact that they play in the same conference(hence some direct comparison), currently rank #52 nationally in total defense, #6 in B10 in total defense, and #38 nationally in points allowed.

Data - I used the 6 metrics used in the diary mentioned above, and compared UM & PSU on a game by game basis during conference play:

a.) Yards/Drive

b.) Stop Percentage - defined as a drive by the opposition that doesn't yield points

c.) Punt Percentage -

d.) 3 and out Percentage

e.) Points/Drive

f.) Didn't put this on the actual chart, but analysis will follow

Format - The following chart lists the the Iowa & Illinois games first based on the fact that both UM & PSU have played both teams(a direct comparison), followed by the game vs. each other. After that, I decided to do a side by side comparision of the UM & PSU defenses according to quality of competition. Ex - comparison of UM's defensive performance against MSU vs. that of PSU's defense against OSU. It would be ill advised to do a side by side comparison of UM's defensive performance against Purdue vs. that of PSU's defensive performance of OSU, etc. Although this certainly doesn't control for variation in competition quality in an absolute manner, it does somewhat cut down the inflation due to inferior opposition.

Results - I think many will be very surprised to see the chart below, and certainly the averages for B10 game will shock some in comparison to PSU. It may suggest that the defense really isn't bad at all.

Game

Yard/Drive

Stop %

Punt %

3 & Out %

Points/Drive

Iowa

MICH

383/11 = 34.8

PSU 349/10=34.9

MICH5/11=45.5

PSU

7/10 = 70

MICH

5/11 = 45.5

PSU

6/10 = 60

MICH

5/11 = 45.5

PSU

3/10 = 30

MICH

38/11 =3.45

PSU

17/10 = 1.7

Illinois

MICH

486/14 = 34.7

PSU 437/9 =48.6

MICH

8/14=57.1

PSU

3/9 = 33.3

MICH

6/14 = 42.8

PSU

2/10 = 20

MICH

4/14 = 28.6

PSU

1/9 = 11.1

MICH

45/14 = 3.2

PSU

26/9 = 2.89

Each Other

MICH

435/9 = 48.3

PSU 423/10=42.3

MICH2/9 = 22.2

PSU

5/10 = 50

MICH

2/9 = 22.2

PSU

3/10 = 30

MICH

1/9 = 11.1

PSU

2/10 = 20

MICH

41/9 = 4.56

PSU

31/10 = 3.1

MICH/MSU

PSU/OSU

MICH

536/10 = 53.6

PSU 453/10=45.3

MICH

4/10 = 40

PSU

6/10 = 60

MICH

4/10 = 40

PSU

4/10 = 40

MICH

2/10 = 20

PSU

2/10 = 20

MICH

34/10 = 3.4

PSU

24/10 = 2.4

MICH/Ind

PSU/NW

MICH

568/13 = 43.7

PSU 369/11=33.6

MICH7/13 = 54

PSU

8/11 = 73

MICH

4/13 = 30.8

PSU

4/11 = 36

MICH

1/13 = 7.7

PSU

4/11 = .36

MICH

35/13 =2.69

PSU

21/11 = 1.9

MICH/Pur

PSU/Minn

MICH

244/15 = 16.3

PSU 433/13=33.3

MICH

12/15 =80

PSU

10/13 =77

MICH

7/15 = 47

PSU

5/13 = 38

MICH

4/15 = 27

PSU

2/13 = .15

MICH

9/15 = .6

PSU

21/13 = 1.6

B10

Averages

MICH2652yds/72drives

= 36.83yds/drive

PSU 2464yds/63drives

=39.11 yds/drive

MICH

38/72=53

PSU

39/63=62

MICH

28/72 = 39

PSU

24/63 = 38

MICH

17/72 = 24

PSU

14/63 = 22

MICH

202/72 =2.81

PSU

140/63 = 2.22

Looking at the above statistics begs the question - how is it that Michigan's defense allows less yards per drive, forces punts at a higher rate, forces 3-and-outs at a higher rate, and yet still they have a lower stop percentage and allow more points per drive?

Now for the all important metric - FIELD POSITION.

Game Average - I accumulated total yards in terms of field position for each game, and divided that by the total number of drives for each game.

B10 average - Simply adding the averages for each game and dividing by number of games would be flawed since each game is weighted differently because the number of possessions in each game varies. I totaled the field position for each individual drive(ex starting at your own 20 would yield an input of 20 yards, while starting at the opposition's 20 would yield an input of 80 yards) of each individual game, and divided by the total number of drives for the duration of B10 games.

Here's the Chart:

UM

Game

Starting Field Position for UM Opposition

Iowa

419/11 = 38.09

Illinois

566/14 = 40.43

PSU

340/9 = 37.78

MSU

301/10 = 30.1

Indiana

342/13 = 26.31

Purdue

539/15 = 35.93

Average

2507/72 = 34.82

PSU

Game

Starting Field Position for PSU Opposition

Iowa

225/10 = 22.5

Illinois

228/9 – 25.33

Michigan

254/10 = 25.4

OSU

253/10 = 25.3

NW

300/11 = 27.27

Minnesota

305/13 = 23.46

Average

1565/63 = 24.8

FACTORS:

Drives per Game - Looking at the stats above, you can see that Michigan's opponents have started 72 drives in 6 games, which means that Michigan's opponents get an avearge of 12 drives per game. On the other hand, PSU's opponents have only had 63 drives for 6 games, an average of 10.5 drives per game. This essentially means that our offense simply scores too quick, and total yards is not a metric for which our defense should be judged by. Since our defense yields an average of 36.83 yards/drive, you would simply multiply 36.83 yards by 1.5, which comes out to 55.24 yards per game that we give up simply because our offense scores quickly. If we used the PSU average of 10.5 drives per game, the defense would allow 378.6 yards per game, which would be good for #64 nationally. For comparison purposes, if PSU opponents averaged 12 drives per game, they would give up 469 yards per game based on their average of 39.11 yards/drive, which would be #120 nationally.

Field Position - special teams and TO's are the things that are most detrimental to our defense right now. The opponents average starting field position against our defense is basically the 35 yard line. We allow on average 36.83 yards per drive. Using the averages, opponents will get to the Michigan 28 yard line on each possession, and that is FG range for most kickers in the B10. Compare that with PSU's defense that allows 39.11 yards per drive, but their opponents starting field position is around the 25 yard line on average. Using the PSU averages, the opponents average drive would end around the PSU 36 yard line, which is not with FG range for most B10 kickers(53yd FG). This explains why our points/drive and stop% metrics are lower than PSU's despite the fact that we win almost every other category.

Conclusion:

Simply put, the defense isn't as bad as we currently think. The defense is put in a position to fail nearly every time they take the field. Whether it is the poor field position that we allow, or TO's, you simply can not allow the opposition to have a 65 yard field and expect good results.

Our offense is so explosive that it puts our defense at a disadvantage because it forces the defense to be on the field for more drives than an average team. Second, with the average field position we allow opponents due to Special Teams and TO's, the stats above indicate that we will yield 3 at least 3 points on almost every drive by the opposition.

What Does This Mean?

Our defense certainly isn't good, but it's not as bad as some think. To be honest, I was shocked at how favorably we stacked up against PSU's defensive numbers. Our defense is in fact approaching average, if the appropriate metrics are used. To use an analogy - basketball defensive statistics are often inflated by teams such as Boston simply because they play a slow game, which means the opposition doesn't have as many FG attempts, and hence a lower point total. A more realistic portrayal of a particular defense is FG% and points per possession.

The same can be said for Michigan's defense, we need to use metrics such as yards per drive, and take field position into account as well in order to get a true guage of their performance.

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Piggybacking off yours and another's who said that coaches were going for it on 4th down more often. Doesn't field position make this decision. If coaches are 10 yards further back those decisions become much harder. IE that 4 th and 4 from the 35 is from the 45 and the 4th and 1 from the 50 is 4th and 1 from your own 40.

Kicking problems, and the offenses's sometimes feast or famine style puts the defense in some bad positions.

At the risk of getting MGoCrucified: The problem is that, due to turnovers, the M offense is seemingly getting more average as well except, in that case, it's a bad thing. Hence losing to Iowa after a decent defensive outing.

I am inclined to agree with you. However, I seem to remember Brian debunking this theory by pointing out that we actually have an average number of possessions per game. Perhaps Penn State is below average? Is that analysis from Brian (or perhaps another diary entry) outdated?

PSU's defensive performance in conference play is pretty bad. They performed very well out of conference (save the Alabama game), which is making their season averages seem decent. In conference play, they really haven't been that good - particularly on the ground.

One part of me thinks it makes sense since the season is winding down for our young D. At some point things have to start clicking after so many games right? I'm not saying our defense is good, but I have seen progress.

The other part of me knows that the Illini offense wasn't that good and Purdue's offense is just plain bad.

I think this weekend's game will be a good measuring stick for our defense. Wiscy's offense can hang with any top defense in the nation.

I really like what you've done here. I do think the amount of optimism needs to be tempered with the fact that you only reference PSU as a comparison, however.

It is definitely hurting our D that we put them in so many bad situations with turnovers and special teams. But they haven't exactly helped by creating turnovers of their own. How many drives has our offense started in good field position this year?

On the other hand, does good field position for our opponents limit their yardage? Length of drive is only limited by starting point at times with our D. I just think to say we are approaching average is nuts and am looking for a reason other than being an eye witness to explain it.

When you take into account that our defense allows 36.83 yards per drive, the only way it would "shorten" the oppositions drives on average would be if the opposition started inside the Michigan 35 yard line.

The field position kills us in terms of points/drive - essentially the opposition only has to pick up 35 yards to get within field goal range, and since we give up an average of 36.83, you can obviously see the consequences that result accordingly. This is why the discrepancy exists between PSU allowing a lower points/drive ratio despite the fact that they allow more yards per drive on average.

The team has progressed enough to take care of business against Illinois and Purdue. Next year, they will have to add a few more teams to that list. The defense will get better with experience. Better special teams will help, too. Hopefully, RR can get a few QC guys back next year to work with the defense and kicking game.

I believe one of the kickers will emerge next year. Hagerup will just become Zoltan 2.0 if he keeps banging 72 yarders! I think we can get one of the last two games, if we don't turn the ball over. Good times for us Michigan fans! I would prefer to beat the suckeyes!

Most of these are all per game metrics. What would it look like on a per possession?

I agree with premise that this D isn't great (and likely not exactly good), but if our games are averaging 33% more possessions than the average, our D should be giving 33% more yards and points on average.

I assume you base that soley on the fact that you played Stanford? I admit that trumps Iowa.

... Otherwise I see the UM schedule as comparing favorably (even as of now)... Navy and Tulsa have 3 losses despite ridiculously easy schedules... Utah just got exposed by TCU and then ND (their biggest win was over Pitt). They'll probably fall out of the rankings even if they win this week at San Diego State. Overrated would be putting it mildly.

Your second toughest game this year (that UM doesn't share) probably comes in two weeks against an unranked USC.

The offense does put the defense on the field at a faster rate. The offense sputters when it shouldn't be, and three and outs puts those guys right back out there. But the defense needs to produce more three and outs themselves. Holding teams to 3rd and 11, then giving up 25 yards doesn't make for a good defense ever!

There should be a real infuses on DE and LB in this years recruiting class, as well as a new defensive coordinator. Someone who will bring real enthusiasm to a low octane defense. Someone who will make this defense a punishing defense.

That would've tainted the numbers when comparing the defense to an "average" defense such as PSU, especially in terms of points/drive, considering that most teams score at least a FG in the overtime due to field position.

Combining all the big ten games minus Purdue, the opposition had 372 plays on offense total. Out of that 372 plays we forced 21 punts, 2 t/o, gave up 8 field goals, and 24 tds. Thats not very good guys.

As far as the Purdue game went they had 69 plays on offense. Out of those 69 plays we forced them to punt 7 times, had 5 t/0's 3 f/gs and 1 td. Those are deffinately better numbers but just keep in mind who we were going up against.

Don't get me wrong, I will take anything I can get to improve our numbers overall, lets just keep things in perspective alittle bit.